valve spring pressures, can we talk about this? |
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valve spring pressures, can we talk about this? |
brer |
Feb 21 2007, 11:51 AM
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#1
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Advanced Member Group: Members Posts: 2,555 Joined: 10-March 05 From: san diego Member No.: 3,736 Region Association: None |
I'm interested in spring pressure preferences and the ideas surrounding them.
installed height seat pressure open pressures dual single beehives maybe the best place to start would be stock. would someone like to throw that in, and maybe an opinion as to why it is good/bad? |
brer |
Feb 28 2007, 06:31 PM
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#2
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Advanced Member Group: Members Posts: 2,555 Joined: 10-March 05 From: san diego Member No.: 3,736 Region Association: None |
so how about stock installed heights and pressure
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bd1308 |
Feb 28 2007, 09:42 PM
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#3
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Sir Post-a-lot Group: Members Posts: 8,020 Joined: 24-January 05 From: Louisville,KY Member No.: 3,501 |
Some of the questions you request are regarded as highly secretive--not many people are willing to divulge details on creating a more bullet-proof engine
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McMark |
Feb 28 2007, 09:48 PM
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#4
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914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
Installed heights are more about seat/valve grinding than spring pressure.
Also, look at variable rate valve springs. (IMG:style_emoticons/default/wink.gif) The factory manual states 160-185 lbs springs. |
brer |
Feb 28 2007, 10:38 PM
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#5
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Advanced Member Group: Members Posts: 2,555 Joined: 10-March 05 From: san diego Member No.: 3,736 Region Association: None |
Some of the questions you request are regarded as highly secretive--not many people are willing to divulge details on creating a more bullet-proof engine that seems like the case I guess. Now that we've broken the seal on this box hopefully some will contribute. Keep your sources. I dont care. But there must be a level of knowledge here that can be discussed without giving away secrets. No big deal right? (IMG:style_emoticons/default/beer.gif) or we can do this the hard way. (IMG:style_emoticons/default/smash.gif) |
bd1308 |
Mar 1 2007, 01:14 AM
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#6
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Sir Post-a-lot Group: Members Posts: 8,020 Joined: 24-January 05 From: Louisville,KY Member No.: 3,501 |
It's sad this knowledge isnt more freely passed on between aircooled engine builders.....
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brer |
Mar 1 2007, 01:26 AM
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#7
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Advanced Member Group: Members Posts: 2,555 Joined: 10-March 05 From: san diego Member No.: 3,736 Region Association: None |
I have some info,.
and sources for cool stuff. Its amazing how free discussion is about this in the subaru forum I read. custom beehives super alloy made to order valves 6mm stems when I can cover ground on this subject i'll post it. and you all should too. (IMG:style_emoticons/default/flag.gif) |
Bleyseng |
Mar 1 2007, 10:02 AM
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#8
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Aircooled Baby! Group: Members Posts: 13,035 Joined: 27-December 02 From: Seattle, Washington (for now) Member No.: 24 Region Association: Pacific Northwest |
Well, it just that the thinking has changed recently. We used to install HD dual springs in order to be able to rev high. That caused problems elsewhere in the cam,lifters as high pressure results in high friction too. Plus the high pressure slams the valves shut which beats the seats into the head.
Now, the thinking is lighter valve train parts with less spring pressures to rev higher equals a engine that revs without so much abuse on the cam/lifters/heads. This is one reason Jake is going with a roller lifter/cam combo so he can reduce the stress/friction of the valve train to rev higher. |
Jake Raby |
Mar 1 2007, 10:40 AM
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#9
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Engine Surgeon Group: Members Posts: 9,394 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
I take it that you guys didn't listen to my valvetrain radio show back in 2006....
It costs us thousands of dollars to gain information and thats not easy or smart to give away! |
brer |
Mar 1 2007, 10:51 AM
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#10
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Advanced Member Group: Members Posts: 2,555 Joined: 10-March 05 From: san diego Member No.: 3,736 Region Association: None |
height pressure
1.450 90lbs 1.350 122 1.150 185 0.950 255 0.875 bind accomodates up to about .520 lift 1.100 bottom O.D. spring mass 42g installed height on my 2L Type 4 1.5 so it looks like with a little shimming I could run this spring with not far off stock seat pressures. with .5 or so of lift (still waiting on my cam specs) I'd be looking at 250lbs Since the shift is towards lighter components then the old way of thinking.. meaning heavy springs and such should no longer be "classified" right. (IMG:style_emoticons/default/laugh.gif) what did people used to think? lets talk about it! (IMG:style_emoticons/default/smile.gif) |
brer |
Mar 1 2007, 10:56 AM
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#11
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Advanced Member Group: Members Posts: 2,555 Joined: 10-March 05 From: san diego Member No.: 3,736 Region Association: None |
I take it that you guys didn't listen to my valvetrain radio show back in 2006.... It costs us thousands of dollars to gain information and thats not easy or smart to give away! no one expects you to give away the good stuff. (IMG:style_emoticons/default/smile.gif) there is a level of information that should be discussed though. otherwise the interest in type 4's will dwindle instead of grow IMO. |
Bleyseng |
Mar 1 2007, 12:43 PM
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#12
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Aircooled Baby! Group: Members Posts: 13,035 Joined: 27-December 02 From: Seattle, Washington (for now) Member No.: 24 Region Association: Pacific Northwest |
I kinda like racing against the guys that still get their engines done by local guys who do stuff like in the 80's. They brag about their big motors, high lift cams, dual modo valve springs, huge 48x40 valves and suffer many mechanical breakdowns with typical problems - dropped valve seats etc. (IMG:style_emoticons/default/biggrin.gif)
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brer |
Mar 1 2007, 01:14 PM
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#13
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Advanced Member Group: Members Posts: 2,555 Joined: 10-March 05 From: san diego Member No.: 3,736 Region Association: None |
so what was the worst valve size/spring combo that used to be Hot.
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bd1308 |
Mar 1 2007, 02:06 PM
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#14
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Sir Post-a-lot Group: Members Posts: 8,020 Joined: 24-January 05 From: Louisville,KY Member No.: 3,501 |
I'm not wanting info on secret new innovative developments--
Just stock info would be great |
brer |
Mar 1 2007, 08:11 PM
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#15
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Advanced Member Group: Members Posts: 2,555 Joined: 10-March 05 From: san diego Member No.: 3,736 Region Association: None |
when i have that info i'll post it.
along with some other things. |
brer |
Mar 2 2007, 01:59 AM
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#16
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Advanced Member Group: Members Posts: 2,555 Joined: 10-March 05 From: san diego Member No.: 3,736 Region Association: None |
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bd1308 |
Mar 2 2007, 08:35 AM
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#17
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Sir Post-a-lot Group: Members Posts: 8,020 Joined: 24-January 05 From: Louisville,KY Member No.: 3,501 |
Obi Wan Brernobi, you're my only hope
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Jake Raby |
Mar 2 2007, 10:15 AM
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#18
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Engine Surgeon Group: Members Posts: 9,394 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
I now share all the data like this on my forum, if we do share it..
I'll be more than happy to share anything with anyone, thats why I offer consultation services. Yes, even stock specs are hard to find that have any amount of research put into them for validity and understanding. The valve train of the type 4 engine is its most important reliability and longevity aspect, giving information pertinent to it's operation opens the doors for guys like our old shadow Stromberg to copy and paste it to their own sites and use it against us in the future. I personally don't prefer to train my future rivals. |
bd1308 |
Mar 2 2007, 10:55 AM
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#19
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Sir Post-a-lot Group: Members Posts: 8,020 Joined: 24-January 05 From: Louisville,KY Member No.: 3,501 |
no but I feel that stock information wouldn't hurt anybody's business--since there are many who dont use stock technology anymore.
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Jake Raby |
Mar 2 2007, 11:13 AM
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#20
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Engine Surgeon Group: Members Posts: 9,394 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
What is "Stock" exactly???
What specs are you looking for? |
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